With a market that constantly hungers for smaller, faster, and cheaper electronics, the ability for Si transistor technology to continue to satisfy the demands will soon reach its end. Marvelous innovations, such as strained Si, have enabled engineers to continue to shrink Si transistors while maintaining reasonable device performance. However, heat dissipation is becoming a critical problem with advanced electronic chips, and many researchers are looking for salvation to come from the integration of new nanomaterials into transistor technology. Carbon nanotubes (CNTs) are one of the leading candidates for transistor applications. CNTs are nanosized cylinders of a couple of nanometers in diameter with such intriguing features as zero-resistance (ballistic) transport of electric current and an exceptional ability to transfer heat. For these, and many other reasons, CNTs would provide excellent channels for the next generation transistors. However, several obstacles remain to be resolved in the growth and placement of CNTs, and these issues currently hinder the ability to readily integrate them into advanced electronics.
In addition to the transistor, myriad other device applications exist for which CNTs are promising candidates. Their surface atoms, which are arranged in a honeycomb lattice, provide excellent sensitivity to charge-transferring molecules, enabling them to increase the sensitivity in biological sensing applications. The robust electrical properties of CNTs, such as the ability to carry an order of magnitude more current per unit area than copper, make them viable for use in low-power electron emission applications, such as those used to make flat-panel televisions. Integration of CNTs into many other applications, from noise thermometers to antennas, is being actively explored for the unique improvements that are possible when using the intrinsic properties of this nanoscale material.